1 /* 2 * GlusterFS backend for QEMU 3 * 4 * Copyright (C) 2012 Bharata B Rao <bharata@linux.vnet.ibm.com> 5 * 6 * This work is licensed under the terms of the GNU GPL, version 2 or later. 7 * See the COPYING file in the top-level directory. 8 * 9 */ 10 11 #include "qemu/osdep.h" 12 #include "qemu/units.h" 13 #include <glusterfs/api/glfs.h> 14 #include "block/block_int.h" 15 #include "block/qdict.h" 16 #include "qapi/error.h" 17 #include "qapi/qmp/qdict.h" 18 #include "qapi/qmp/qerror.h" 19 #include "qemu/uri.h" 20 #include "qemu/error-report.h" 21 #include "qemu/module.h" 22 #include "qemu/option.h" 23 #include "qemu/cutils.h" 24 25 #ifdef CONFIG_GLUSTERFS_FTRUNCATE_HAS_STAT 26 # define glfs_ftruncate(fd, offset) glfs_ftruncate(fd, offset, NULL, NULL) 27 #endif 28 29 #define GLUSTER_OPT_FILENAME "filename" 30 #define GLUSTER_OPT_VOLUME "volume" 31 #define GLUSTER_OPT_PATH "path" 32 #define GLUSTER_OPT_TYPE "type" 33 #define GLUSTER_OPT_SERVER_PATTERN "server." 34 #define GLUSTER_OPT_HOST "host" 35 #define GLUSTER_OPT_PORT "port" 36 #define GLUSTER_OPT_TO "to" 37 #define GLUSTER_OPT_IPV4 "ipv4" 38 #define GLUSTER_OPT_IPV6 "ipv6" 39 #define GLUSTER_OPT_SOCKET "socket" 40 #define GLUSTER_OPT_DEBUG "debug" 41 #define GLUSTER_DEFAULT_PORT 24007 42 #define GLUSTER_DEBUG_DEFAULT 4 43 #define GLUSTER_DEBUG_MAX 9 44 #define GLUSTER_OPT_LOGFILE "logfile" 45 #define GLUSTER_LOGFILE_DEFAULT "-" /* handled in libgfapi as /dev/stderr */ 46 /* 47 * Several versions of GlusterFS (3.12? -> 6.0.1) fail when the transfer size 48 * is greater or equal to 1024 MiB, so we are limiting the transfer size to 512 49 * MiB to avoid this rare issue. 50 */ 51 #define GLUSTER_MAX_TRANSFER (512 * MiB) 52 53 #define GERR_INDEX_HINT "hint: check in 'server' array index '%d'\n" 54 55 typedef struct GlusterAIOCB { 56 int64_t size; 57 int ret; 58 Coroutine *coroutine; 59 AioContext *aio_context; 60 } GlusterAIOCB; 61 62 typedef struct BDRVGlusterState { 63 struct glfs *glfs; 64 struct glfs_fd *fd; 65 char *logfile; 66 bool supports_seek_data; 67 int debug; 68 } BDRVGlusterState; 69 70 typedef struct BDRVGlusterReopenState { 71 struct glfs *glfs; 72 struct glfs_fd *fd; 73 } BDRVGlusterReopenState; 74 75 76 typedef struct GlfsPreopened { 77 char *volume; 78 glfs_t *fs; 79 int ref; 80 } GlfsPreopened; 81 82 typedef struct ListElement { 83 QLIST_ENTRY(ListElement) list; 84 GlfsPreopened saved; 85 } ListElement; 86 87 static QLIST_HEAD(, ListElement) glfs_list; 88 89 static QemuOptsList qemu_gluster_create_opts = { 90 .name = "qemu-gluster-create-opts", 91 .head = QTAILQ_HEAD_INITIALIZER(qemu_gluster_create_opts.head), 92 .desc = { 93 { 94 .name = BLOCK_OPT_SIZE, 95 .type = QEMU_OPT_SIZE, 96 .help = "Virtual disk size" 97 }, 98 { 99 .name = BLOCK_OPT_PREALLOC, 100 .type = QEMU_OPT_STRING, 101 .help = "Preallocation mode (allowed values: off" 102 #ifdef CONFIG_GLUSTERFS_FALLOCATE 103 ", falloc" 104 #endif 105 #ifdef CONFIG_GLUSTERFS_ZEROFILL 106 ", full" 107 #endif 108 ")" 109 }, 110 { 111 .name = GLUSTER_OPT_DEBUG, 112 .type = QEMU_OPT_NUMBER, 113 .help = "Gluster log level, valid range is 0-9", 114 }, 115 { 116 .name = GLUSTER_OPT_LOGFILE, 117 .type = QEMU_OPT_STRING, 118 .help = "Logfile path of libgfapi", 119 }, 120 { /* end of list */ } 121 } 122 }; 123 124 static QemuOptsList runtime_opts = { 125 .name = "gluster", 126 .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head), 127 .desc = { 128 { 129 .name = GLUSTER_OPT_FILENAME, 130 .type = QEMU_OPT_STRING, 131 .help = "URL to the gluster image", 132 }, 133 { 134 .name = GLUSTER_OPT_DEBUG, 135 .type = QEMU_OPT_NUMBER, 136 .help = "Gluster log level, valid range is 0-9", 137 }, 138 { 139 .name = GLUSTER_OPT_LOGFILE, 140 .type = QEMU_OPT_STRING, 141 .help = "Logfile path of libgfapi", 142 }, 143 { /* end of list */ } 144 }, 145 }; 146 147 static QemuOptsList runtime_json_opts = { 148 .name = "gluster_json", 149 .head = QTAILQ_HEAD_INITIALIZER(runtime_json_opts.head), 150 .desc = { 151 { 152 .name = GLUSTER_OPT_VOLUME, 153 .type = QEMU_OPT_STRING, 154 .help = "name of gluster volume where VM image resides", 155 }, 156 { 157 .name = GLUSTER_OPT_PATH, 158 .type = QEMU_OPT_STRING, 159 .help = "absolute path to image file in gluster volume", 160 }, 161 { 162 .name = GLUSTER_OPT_DEBUG, 163 .type = QEMU_OPT_NUMBER, 164 .help = "Gluster log level, valid range is 0-9", 165 }, 166 { /* end of list */ } 167 }, 168 }; 169 170 static QemuOptsList runtime_type_opts = { 171 .name = "gluster_type", 172 .head = QTAILQ_HEAD_INITIALIZER(runtime_type_opts.head), 173 .desc = { 174 { 175 .name = GLUSTER_OPT_TYPE, 176 .type = QEMU_OPT_STRING, 177 .help = "inet|unix", 178 }, 179 { /* end of list */ } 180 }, 181 }; 182 183 static QemuOptsList runtime_unix_opts = { 184 .name = "gluster_unix", 185 .head = QTAILQ_HEAD_INITIALIZER(runtime_unix_opts.head), 186 .desc = { 187 { 188 .name = GLUSTER_OPT_SOCKET, 189 .type = QEMU_OPT_STRING, 190 .help = "socket file path (legacy)", 191 }, 192 { 193 .name = GLUSTER_OPT_PATH, 194 .type = QEMU_OPT_STRING, 195 .help = "socket file path (QAPI)", 196 }, 197 { /* end of list */ } 198 }, 199 }; 200 201 static QemuOptsList runtime_inet_opts = { 202 .name = "gluster_inet", 203 .head = QTAILQ_HEAD_INITIALIZER(runtime_inet_opts.head), 204 .desc = { 205 { 206 .name = GLUSTER_OPT_TYPE, 207 .type = QEMU_OPT_STRING, 208 .help = "inet|unix", 209 }, 210 { 211 .name = GLUSTER_OPT_HOST, 212 .type = QEMU_OPT_STRING, 213 .help = "host address (hostname/ipv4/ipv6 addresses)", 214 }, 215 { 216 .name = GLUSTER_OPT_PORT, 217 .type = QEMU_OPT_STRING, 218 .help = "port number on which glusterd is listening (default 24007)", 219 }, 220 { 221 .name = "to", 222 .type = QEMU_OPT_NUMBER, 223 .help = "max port number, not supported by gluster", 224 }, 225 { 226 .name = "ipv4", 227 .type = QEMU_OPT_BOOL, 228 .help = "ipv4 bool value, not supported by gluster", 229 }, 230 { 231 .name = "ipv6", 232 .type = QEMU_OPT_BOOL, 233 .help = "ipv6 bool value, not supported by gluster", 234 }, 235 { /* end of list */ } 236 }, 237 }; 238 239 static void glfs_set_preopened(const char *volume, glfs_t *fs) 240 { 241 ListElement *entry = NULL; 242 243 entry = g_new(ListElement, 1); 244 245 entry->saved.volume = g_strdup(volume); 246 247 entry->saved.fs = fs; 248 entry->saved.ref = 1; 249 250 QLIST_INSERT_HEAD(&glfs_list, entry, list); 251 } 252 253 static glfs_t *glfs_find_preopened(const char *volume) 254 { 255 ListElement *entry = NULL; 256 257 QLIST_FOREACH(entry, &glfs_list, list) { 258 if (strcmp(entry->saved.volume, volume) == 0) { 259 entry->saved.ref++; 260 return entry->saved.fs; 261 } 262 } 263 264 return NULL; 265 } 266 267 static void glfs_clear_preopened(glfs_t *fs) 268 { 269 ListElement *entry = NULL; 270 ListElement *next; 271 272 if (fs == NULL) { 273 return; 274 } 275 276 QLIST_FOREACH_SAFE(entry, &glfs_list, list, next) { 277 if (entry->saved.fs == fs) { 278 if (--entry->saved.ref) { 279 return; 280 } 281 282 QLIST_REMOVE(entry, list); 283 284 glfs_fini(entry->saved.fs); 285 g_free(entry->saved.volume); 286 g_free(entry); 287 } 288 } 289 } 290 291 static int parse_volume_options(BlockdevOptionsGluster *gconf, char *path) 292 { 293 char *p, *q; 294 295 if (!path) { 296 return -EINVAL; 297 } 298 299 /* volume */ 300 p = q = path + strspn(path, "/"); 301 p += strcspn(p, "/"); 302 if (*p == '\0') { 303 return -EINVAL; 304 } 305 gconf->volume = g_strndup(q, p - q); 306 307 /* path */ 308 p += strspn(p, "/"); 309 if (*p == '\0') { 310 return -EINVAL; 311 } 312 gconf->path = g_strdup(p); 313 return 0; 314 } 315 316 /* 317 * file=gluster[+transport]://[host[:port]]/volume/path[?socket=...] 318 * 319 * 'gluster' is the protocol. 320 * 321 * 'transport' specifies the transport type used to connect to gluster 322 * management daemon (glusterd). Valid transport types are 323 * tcp or unix. If a transport type isn't specified, then tcp type is assumed. 324 * 325 * 'host' specifies the host where the volume file specification for 326 * the given volume resides. This can be either hostname or ipv4 address. 327 * If transport type is 'unix', then 'host' field should not be specified. 328 * The 'socket' field needs to be populated with the path to unix domain 329 * socket. 330 * 331 * 'port' is the port number on which glusterd is listening. This is optional 332 * and if not specified, QEMU will send 0 which will make gluster to use the 333 * default port. If the transport type is unix, then 'port' should not be 334 * specified. 335 * 336 * 'volume' is the name of the gluster volume which contains the VM image. 337 * 338 * 'path' is the path to the actual VM image that resides on gluster volume. 339 * 340 * Examples: 341 * 342 * file=gluster://1.2.3.4/testvol/a.img 343 * file=gluster+tcp://1.2.3.4/testvol/a.img 344 * file=gluster+tcp://1.2.3.4:24007/testvol/dir/a.img 345 * file=gluster+tcp://host.domain.com:24007/testvol/dir/a.img 346 * file=gluster+unix:///testvol/dir/a.img?socket=/tmp/glusterd.socket 347 */ 348 static int qemu_gluster_parse_uri(BlockdevOptionsGluster *gconf, 349 const char *filename) 350 { 351 SocketAddress *gsconf; 352 URI *uri; 353 QueryParams *qp = NULL; 354 bool is_unix = false; 355 int ret = 0; 356 357 uri = uri_parse(filename); 358 if (!uri) { 359 return -EINVAL; 360 } 361 362 gconf->server = g_new0(SocketAddressList, 1); 363 gconf->server->value = gsconf = g_new0(SocketAddress, 1); 364 365 /* transport */ 366 if (!uri->scheme || !strcmp(uri->scheme, "gluster")) { 367 gsconf->type = SOCKET_ADDRESS_TYPE_INET; 368 } else if (!strcmp(uri->scheme, "gluster+tcp")) { 369 gsconf->type = SOCKET_ADDRESS_TYPE_INET; 370 } else if (!strcmp(uri->scheme, "gluster+unix")) { 371 gsconf->type = SOCKET_ADDRESS_TYPE_UNIX; 372 is_unix = true; 373 } else if (!strcmp(uri->scheme, "gluster+rdma")) { 374 gsconf->type = SOCKET_ADDRESS_TYPE_INET; 375 warn_report("rdma feature is not supported, falling back to tcp"); 376 } else { 377 ret = -EINVAL; 378 goto out; 379 } 380 381 ret = parse_volume_options(gconf, uri->path); 382 if (ret < 0) { 383 goto out; 384 } 385 386 qp = query_params_parse(uri->query); 387 if (qp->n > 1 || (is_unix && !qp->n) || (!is_unix && qp->n)) { 388 ret = -EINVAL; 389 goto out; 390 } 391 392 if (is_unix) { 393 if (uri->server || uri->port) { 394 ret = -EINVAL; 395 goto out; 396 } 397 if (strcmp(qp->p[0].name, "socket")) { 398 ret = -EINVAL; 399 goto out; 400 } 401 gsconf->u.q_unix.path = g_strdup(qp->p[0].value); 402 } else { 403 gsconf->u.inet.host = g_strdup(uri->server ? uri->server : "localhost"); 404 if (uri->port) { 405 gsconf->u.inet.port = g_strdup_printf("%d", uri->port); 406 } else { 407 gsconf->u.inet.port = g_strdup_printf("%d", GLUSTER_DEFAULT_PORT); 408 } 409 } 410 411 out: 412 if (qp) { 413 query_params_free(qp); 414 } 415 uri_free(uri); 416 return ret; 417 } 418 419 static struct glfs *qemu_gluster_glfs_init(BlockdevOptionsGluster *gconf, 420 Error **errp) 421 { 422 struct glfs *glfs; 423 int ret; 424 int old_errno; 425 SocketAddressList *server; 426 unsigned long long port; 427 428 glfs = glfs_find_preopened(gconf->volume); 429 if (glfs) { 430 return glfs; 431 } 432 433 glfs = glfs_new(gconf->volume); 434 if (!glfs) { 435 goto out; 436 } 437 438 glfs_set_preopened(gconf->volume, glfs); 439 440 for (server = gconf->server; server; server = server->next) { 441 switch (server->value->type) { 442 case SOCKET_ADDRESS_TYPE_UNIX: 443 ret = glfs_set_volfile_server(glfs, "unix", 444 server->value->u.q_unix.path, 0); 445 break; 446 case SOCKET_ADDRESS_TYPE_INET: 447 if (parse_uint_full(server->value->u.inet.port, &port, 10) < 0 || 448 port > 65535) { 449 error_setg(errp, "'%s' is not a valid port number", 450 server->value->u.inet.port); 451 errno = EINVAL; 452 goto out; 453 } 454 ret = glfs_set_volfile_server(glfs, "tcp", 455 server->value->u.inet.host, 456 (int)port); 457 break; 458 case SOCKET_ADDRESS_TYPE_VSOCK: 459 case SOCKET_ADDRESS_TYPE_FD: 460 default: 461 abort(); 462 } 463 464 if (ret < 0) { 465 goto out; 466 } 467 } 468 469 ret = glfs_set_logging(glfs, gconf->logfile, gconf->debug); 470 if (ret < 0) { 471 goto out; 472 } 473 474 ret = glfs_init(glfs); 475 if (ret) { 476 error_setg(errp, "Gluster connection for volume %s, path %s failed" 477 " to connect", gconf->volume, gconf->path); 478 for (server = gconf->server; server; server = server->next) { 479 if (server->value->type == SOCKET_ADDRESS_TYPE_UNIX) { 480 error_append_hint(errp, "hint: failed on socket %s ", 481 server->value->u.q_unix.path); 482 } else { 483 error_append_hint(errp, "hint: failed on host %s and port %s ", 484 server->value->u.inet.host, 485 server->value->u.inet.port); 486 } 487 } 488 489 error_append_hint(errp, "Please refer to gluster logs for more info\n"); 490 491 /* glfs_init sometimes doesn't set errno although docs suggest that */ 492 if (errno == 0) { 493 errno = EINVAL; 494 } 495 496 goto out; 497 } 498 return glfs; 499 500 out: 501 if (glfs) { 502 old_errno = errno; 503 glfs_clear_preopened(glfs); 504 errno = old_errno; 505 } 506 return NULL; 507 } 508 509 /* 510 * Convert the json formatted command line into qapi. 511 */ 512 static int qemu_gluster_parse_json(BlockdevOptionsGluster *gconf, 513 QDict *options, Error **errp) 514 { 515 QemuOpts *opts; 516 SocketAddress *gsconf = NULL; 517 SocketAddressList *curr = NULL; 518 QDict *backing_options = NULL; 519 Error *local_err = NULL; 520 char *str = NULL; 521 const char *ptr; 522 int i, type, num_servers; 523 524 /* create opts info from runtime_json_opts list */ 525 opts = qemu_opts_create(&runtime_json_opts, NULL, 0, &error_abort); 526 qemu_opts_absorb_qdict(opts, options, &local_err); 527 if (local_err) { 528 goto out; 529 } 530 531 num_servers = qdict_array_entries(options, GLUSTER_OPT_SERVER_PATTERN); 532 if (num_servers < 1) { 533 error_setg(&local_err, QERR_MISSING_PARAMETER, "server"); 534 goto out; 535 } 536 537 ptr = qemu_opt_get(opts, GLUSTER_OPT_VOLUME); 538 if (!ptr) { 539 error_setg(&local_err, QERR_MISSING_PARAMETER, GLUSTER_OPT_VOLUME); 540 goto out; 541 } 542 gconf->volume = g_strdup(ptr); 543 544 ptr = qemu_opt_get(opts, GLUSTER_OPT_PATH); 545 if (!ptr) { 546 error_setg(&local_err, QERR_MISSING_PARAMETER, GLUSTER_OPT_PATH); 547 goto out; 548 } 549 gconf->path = g_strdup(ptr); 550 qemu_opts_del(opts); 551 552 for (i = 0; i < num_servers; i++) { 553 str = g_strdup_printf(GLUSTER_OPT_SERVER_PATTERN"%d.", i); 554 qdict_extract_subqdict(options, &backing_options, str); 555 556 /* create opts info from runtime_type_opts list */ 557 opts = qemu_opts_create(&runtime_type_opts, NULL, 0, &error_abort); 558 qemu_opts_absorb_qdict(opts, backing_options, &local_err); 559 if (local_err) { 560 goto out; 561 } 562 563 ptr = qemu_opt_get(opts, GLUSTER_OPT_TYPE); 564 if (!ptr) { 565 error_setg(&local_err, QERR_MISSING_PARAMETER, GLUSTER_OPT_TYPE); 566 error_append_hint(&local_err, GERR_INDEX_HINT, i); 567 goto out; 568 569 } 570 gsconf = g_new0(SocketAddress, 1); 571 if (!strcmp(ptr, "tcp")) { 572 ptr = "inet"; /* accept legacy "tcp" */ 573 } 574 type = qapi_enum_parse(&SocketAddressType_lookup, ptr, -1, NULL); 575 if (type != SOCKET_ADDRESS_TYPE_INET 576 && type != SOCKET_ADDRESS_TYPE_UNIX) { 577 error_setg(&local_err, 578 "Parameter '%s' may be 'inet' or 'unix'", 579 GLUSTER_OPT_TYPE); 580 error_append_hint(&local_err, GERR_INDEX_HINT, i); 581 goto out; 582 } 583 gsconf->type = type; 584 qemu_opts_del(opts); 585 586 if (gsconf->type == SOCKET_ADDRESS_TYPE_INET) { 587 /* create opts info from runtime_inet_opts list */ 588 opts = qemu_opts_create(&runtime_inet_opts, NULL, 0, &error_abort); 589 qemu_opts_absorb_qdict(opts, backing_options, &local_err); 590 if (local_err) { 591 goto out; 592 } 593 594 ptr = qemu_opt_get(opts, GLUSTER_OPT_HOST); 595 if (!ptr) { 596 error_setg(&local_err, QERR_MISSING_PARAMETER, 597 GLUSTER_OPT_HOST); 598 error_append_hint(&local_err, GERR_INDEX_HINT, i); 599 goto out; 600 } 601 gsconf->u.inet.host = g_strdup(ptr); 602 ptr = qemu_opt_get(opts, GLUSTER_OPT_PORT); 603 if (!ptr) { 604 error_setg(&local_err, QERR_MISSING_PARAMETER, 605 GLUSTER_OPT_PORT); 606 error_append_hint(&local_err, GERR_INDEX_HINT, i); 607 goto out; 608 } 609 gsconf->u.inet.port = g_strdup(ptr); 610 611 /* defend for unsupported fields in InetSocketAddress, 612 * i.e. @ipv4, @ipv6 and @to 613 */ 614 ptr = qemu_opt_get(opts, GLUSTER_OPT_TO); 615 if (ptr) { 616 gsconf->u.inet.has_to = true; 617 } 618 ptr = qemu_opt_get(opts, GLUSTER_OPT_IPV4); 619 if (ptr) { 620 gsconf->u.inet.has_ipv4 = true; 621 } 622 ptr = qemu_opt_get(opts, GLUSTER_OPT_IPV6); 623 if (ptr) { 624 gsconf->u.inet.has_ipv6 = true; 625 } 626 if (gsconf->u.inet.has_to) { 627 error_setg(&local_err, "Parameter 'to' not supported"); 628 goto out; 629 } 630 if (gsconf->u.inet.has_ipv4 || gsconf->u.inet.has_ipv6) { 631 error_setg(&local_err, "Parameters 'ipv4/ipv6' not supported"); 632 goto out; 633 } 634 qemu_opts_del(opts); 635 } else { 636 /* create opts info from runtime_unix_opts list */ 637 opts = qemu_opts_create(&runtime_unix_opts, NULL, 0, &error_abort); 638 qemu_opts_absorb_qdict(opts, backing_options, &local_err); 639 if (local_err) { 640 goto out; 641 } 642 643 ptr = qemu_opt_get(opts, GLUSTER_OPT_PATH); 644 if (!ptr) { 645 ptr = qemu_opt_get(opts, GLUSTER_OPT_SOCKET); 646 } else if (qemu_opt_get(opts, GLUSTER_OPT_SOCKET)) { 647 error_setg(&local_err, 648 "Conflicting parameters 'path' and 'socket'"); 649 error_append_hint(&local_err, GERR_INDEX_HINT, i); 650 goto out; 651 } 652 if (!ptr) { 653 error_setg(&local_err, QERR_MISSING_PARAMETER, 654 GLUSTER_OPT_PATH); 655 error_append_hint(&local_err, GERR_INDEX_HINT, i); 656 goto out; 657 } 658 gsconf->u.q_unix.path = g_strdup(ptr); 659 qemu_opts_del(opts); 660 } 661 662 if (gconf->server == NULL) { 663 gconf->server = g_new0(SocketAddressList, 1); 664 gconf->server->value = gsconf; 665 curr = gconf->server; 666 } else { 667 curr->next = g_new0(SocketAddressList, 1); 668 curr->next->value = gsconf; 669 curr = curr->next; 670 } 671 gsconf = NULL; 672 673 qobject_unref(backing_options); 674 backing_options = NULL; 675 g_free(str); 676 str = NULL; 677 } 678 679 return 0; 680 681 out: 682 error_propagate(errp, local_err); 683 qapi_free_SocketAddress(gsconf); 684 qemu_opts_del(opts); 685 g_free(str); 686 qobject_unref(backing_options); 687 errno = EINVAL; 688 return -errno; 689 } 690 691 /* Converts options given in @filename and the @options QDict into the QAPI 692 * object @gconf. */ 693 static int qemu_gluster_parse(BlockdevOptionsGluster *gconf, 694 const char *filename, 695 QDict *options, Error **errp) 696 { 697 int ret; 698 if (filename) { 699 ret = qemu_gluster_parse_uri(gconf, filename); 700 if (ret < 0) { 701 error_setg(errp, "invalid URI %s", filename); 702 error_append_hint(errp, "Usage: file=gluster[+transport]://" 703 "[host[:port]]volume/path[?socket=...]" 704 "[,file.debug=N]" 705 "[,file.logfile=/path/filename.log]\n"); 706 return ret; 707 } 708 } else { 709 ret = qemu_gluster_parse_json(gconf, options, errp); 710 if (ret < 0) { 711 error_append_hint(errp, "Usage: " 712 "-drive driver=qcow2,file.driver=gluster," 713 "file.volume=testvol,file.path=/path/a.qcow2" 714 "[,file.debug=9]" 715 "[,file.logfile=/path/filename.log]," 716 "file.server.0.type=inet," 717 "file.server.0.host=1.2.3.4," 718 "file.server.0.port=24007," 719 "file.server.1.transport=unix," 720 "file.server.1.path=/var/run/glusterd.socket ..." 721 "\n"); 722 return ret; 723 } 724 } 725 726 return 0; 727 } 728 729 static struct glfs *qemu_gluster_init(BlockdevOptionsGluster *gconf, 730 const char *filename, 731 QDict *options, Error **errp) 732 { 733 int ret; 734 735 ret = qemu_gluster_parse(gconf, filename, options, errp); 736 if (ret < 0) { 737 errno = -ret; 738 return NULL; 739 } 740 741 return qemu_gluster_glfs_init(gconf, errp); 742 } 743 744 /* 745 * AIO callback routine called from GlusterFS thread. 746 */ 747 static void gluster_finish_aiocb(struct glfs_fd *fd, ssize_t ret, 748 #ifdef CONFIG_GLUSTERFS_IOCB_HAS_STAT 749 struct glfs_stat *pre, struct glfs_stat *post, 750 #endif 751 void *arg) 752 { 753 GlusterAIOCB *acb = (GlusterAIOCB *)arg; 754 755 if (!ret || ret == acb->size) { 756 acb->ret = 0; /* Success */ 757 } else if (ret < 0) { 758 acb->ret = -errno; /* Read/Write failed */ 759 } else { 760 acb->ret = -EIO; /* Partial read/write - fail it */ 761 } 762 763 aio_co_schedule(acb->aio_context, acb->coroutine); 764 } 765 766 static void qemu_gluster_parse_flags(int bdrv_flags, int *open_flags) 767 { 768 assert(open_flags != NULL); 769 770 *open_flags |= O_BINARY; 771 772 if (bdrv_flags & BDRV_O_RDWR) { 773 *open_flags |= O_RDWR; 774 } else { 775 *open_flags |= O_RDONLY; 776 } 777 778 if ((bdrv_flags & BDRV_O_NOCACHE)) { 779 *open_flags |= O_DIRECT; 780 } 781 } 782 783 /* 784 * Do SEEK_DATA/HOLE to detect if it is functional. Older broken versions of 785 * gfapi incorrectly return the current offset when SEEK_DATA/HOLE is used. 786 * - Corrected versions return -1 and set errno to EINVAL. 787 * - Versions that support SEEK_DATA/HOLE correctly, will return -1 and set 788 * errno to ENXIO when SEEK_DATA is called with a position of EOF. 789 */ 790 static bool qemu_gluster_test_seek(struct glfs_fd *fd) 791 { 792 off_t ret = 0; 793 794 #if defined SEEK_HOLE && defined SEEK_DATA 795 off_t eof; 796 797 eof = glfs_lseek(fd, 0, SEEK_END); 798 if (eof < 0) { 799 /* this should never occur */ 800 return false; 801 } 802 803 /* this should always fail with ENXIO if SEEK_DATA is supported */ 804 ret = glfs_lseek(fd, eof, SEEK_DATA); 805 #endif 806 807 return (ret < 0) && (errno == ENXIO); 808 } 809 810 static int qemu_gluster_open(BlockDriverState *bs, QDict *options, 811 int bdrv_flags, Error **errp) 812 { 813 BDRVGlusterState *s = bs->opaque; 814 int open_flags = 0; 815 int ret = 0; 816 BlockdevOptionsGluster *gconf = NULL; 817 QemuOpts *opts; 818 Error *local_err = NULL; 819 const char *filename, *logfile; 820 821 opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort); 822 qemu_opts_absorb_qdict(opts, options, &local_err); 823 if (local_err) { 824 error_propagate(errp, local_err); 825 ret = -EINVAL; 826 goto out; 827 } 828 829 filename = qemu_opt_get(opts, GLUSTER_OPT_FILENAME); 830 831 s->debug = qemu_opt_get_number(opts, GLUSTER_OPT_DEBUG, 832 GLUSTER_DEBUG_DEFAULT); 833 if (s->debug < 0) { 834 s->debug = 0; 835 } else if (s->debug > GLUSTER_DEBUG_MAX) { 836 s->debug = GLUSTER_DEBUG_MAX; 837 } 838 839 gconf = g_new0(BlockdevOptionsGluster, 1); 840 gconf->debug = s->debug; 841 gconf->has_debug = true; 842 843 logfile = qemu_opt_get(opts, GLUSTER_OPT_LOGFILE); 844 s->logfile = g_strdup(logfile ? logfile : GLUSTER_LOGFILE_DEFAULT); 845 846 gconf->logfile = g_strdup(s->logfile); 847 gconf->has_logfile = true; 848 849 s->glfs = qemu_gluster_init(gconf, filename, options, errp); 850 if (!s->glfs) { 851 ret = -errno; 852 goto out; 853 } 854 855 #ifdef CONFIG_GLUSTERFS_XLATOR_OPT 856 /* Without this, if fsync fails for a recoverable reason (for instance, 857 * ENOSPC), gluster will dump its cache, preventing retries. This means 858 * almost certain data loss. Not all gluster versions support the 859 * 'resync-failed-syncs-after-fsync' key value, but there is no way to 860 * discover during runtime if it is supported (this api returns success for 861 * unknown key/value pairs) */ 862 ret = glfs_set_xlator_option(s->glfs, "*-write-behind", 863 "resync-failed-syncs-after-fsync", 864 "on"); 865 if (ret < 0) { 866 error_setg_errno(errp, errno, "Unable to set xlator key/value pair"); 867 ret = -errno; 868 goto out; 869 } 870 #endif 871 872 qemu_gluster_parse_flags(bdrv_flags, &open_flags); 873 874 s->fd = glfs_open(s->glfs, gconf->path, open_flags); 875 ret = s->fd ? 0 : -errno; 876 877 if (ret == -EACCES || ret == -EROFS) { 878 /* Try to degrade to read-only, but if it doesn't work, still use the 879 * normal error message. */ 880 if (bdrv_apply_auto_read_only(bs, NULL, NULL) == 0) { 881 open_flags = (open_flags & ~O_RDWR) | O_RDONLY; 882 s->fd = glfs_open(s->glfs, gconf->path, open_flags); 883 ret = s->fd ? 0 : -errno; 884 } 885 } 886 887 s->supports_seek_data = qemu_gluster_test_seek(s->fd); 888 889 out: 890 qemu_opts_del(opts); 891 qapi_free_BlockdevOptionsGluster(gconf); 892 if (!ret) { 893 return ret; 894 } 895 g_free(s->logfile); 896 if (s->fd) { 897 glfs_close(s->fd); 898 } 899 900 glfs_clear_preopened(s->glfs); 901 902 return ret; 903 } 904 905 static void qemu_gluster_refresh_limits(BlockDriverState *bs, Error **errp) 906 { 907 bs->bl.max_transfer = GLUSTER_MAX_TRANSFER; 908 } 909 910 static int qemu_gluster_reopen_prepare(BDRVReopenState *state, 911 BlockReopenQueue *queue, Error **errp) 912 { 913 int ret = 0; 914 BDRVGlusterState *s; 915 BDRVGlusterReopenState *reop_s; 916 BlockdevOptionsGluster *gconf; 917 int open_flags = 0; 918 919 assert(state != NULL); 920 assert(state->bs != NULL); 921 922 s = state->bs->opaque; 923 924 state->opaque = g_new0(BDRVGlusterReopenState, 1); 925 reop_s = state->opaque; 926 927 qemu_gluster_parse_flags(state->flags, &open_flags); 928 929 gconf = g_new0(BlockdevOptionsGluster, 1); 930 gconf->debug = s->debug; 931 gconf->has_debug = true; 932 gconf->logfile = g_strdup(s->logfile); 933 gconf->has_logfile = true; 934 935 /* 936 * If 'state->bs->exact_filename' is empty, 'state->options' should contain 937 * the JSON parameters already parsed. 938 */ 939 if (state->bs->exact_filename[0] != '\0') { 940 reop_s->glfs = qemu_gluster_init(gconf, state->bs->exact_filename, NULL, 941 errp); 942 } else { 943 reop_s->glfs = qemu_gluster_init(gconf, NULL, state->options, errp); 944 } 945 if (reop_s->glfs == NULL) { 946 ret = -errno; 947 goto exit; 948 } 949 950 #ifdef CONFIG_GLUSTERFS_XLATOR_OPT 951 ret = glfs_set_xlator_option(reop_s->glfs, "*-write-behind", 952 "resync-failed-syncs-after-fsync", "on"); 953 if (ret < 0) { 954 error_setg_errno(errp, errno, "Unable to set xlator key/value pair"); 955 ret = -errno; 956 goto exit; 957 } 958 #endif 959 960 reop_s->fd = glfs_open(reop_s->glfs, gconf->path, open_flags); 961 if (reop_s->fd == NULL) { 962 /* reops->glfs will be cleaned up in _abort */ 963 ret = -errno; 964 goto exit; 965 } 966 967 exit: 968 /* state->opaque will be freed in either the _abort or _commit */ 969 qapi_free_BlockdevOptionsGluster(gconf); 970 return ret; 971 } 972 973 static void qemu_gluster_reopen_commit(BDRVReopenState *state) 974 { 975 BDRVGlusterReopenState *reop_s = state->opaque; 976 BDRVGlusterState *s = state->bs->opaque; 977 978 979 /* close the old */ 980 if (s->fd) { 981 glfs_close(s->fd); 982 } 983 984 glfs_clear_preopened(s->glfs); 985 986 /* use the newly opened image / connection */ 987 s->fd = reop_s->fd; 988 s->glfs = reop_s->glfs; 989 990 g_free(state->opaque); 991 state->opaque = NULL; 992 993 return; 994 } 995 996 997 static void qemu_gluster_reopen_abort(BDRVReopenState *state) 998 { 999 BDRVGlusterReopenState *reop_s = state->opaque; 1000 1001 if (reop_s == NULL) { 1002 return; 1003 } 1004 1005 if (reop_s->fd) { 1006 glfs_close(reop_s->fd); 1007 } 1008 1009 glfs_clear_preopened(reop_s->glfs); 1010 1011 g_free(state->opaque); 1012 state->opaque = NULL; 1013 1014 return; 1015 } 1016 1017 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1018 static coroutine_fn int qemu_gluster_co_pwrite_zeroes(BlockDriverState *bs, 1019 int64_t offset, 1020 int size, 1021 BdrvRequestFlags flags) 1022 { 1023 int ret; 1024 GlusterAIOCB acb; 1025 BDRVGlusterState *s = bs->opaque; 1026 1027 acb.size = size; 1028 acb.ret = 0; 1029 acb.coroutine = qemu_coroutine_self(); 1030 acb.aio_context = bdrv_get_aio_context(bs); 1031 1032 ret = glfs_zerofill_async(s->fd, offset, size, gluster_finish_aiocb, &acb); 1033 if (ret < 0) { 1034 return -errno; 1035 } 1036 1037 qemu_coroutine_yield(); 1038 return acb.ret; 1039 } 1040 #endif 1041 1042 static int qemu_gluster_do_truncate(struct glfs_fd *fd, int64_t offset, 1043 PreallocMode prealloc, Error **errp) 1044 { 1045 int64_t current_length; 1046 1047 current_length = glfs_lseek(fd, 0, SEEK_END); 1048 if (current_length < 0) { 1049 error_setg_errno(errp, errno, "Failed to determine current size"); 1050 return -errno; 1051 } 1052 1053 if (current_length > offset && prealloc != PREALLOC_MODE_OFF) { 1054 error_setg(errp, "Cannot use preallocation for shrinking files"); 1055 return -ENOTSUP; 1056 } 1057 1058 if (current_length == offset) { 1059 return 0; 1060 } 1061 1062 switch (prealloc) { 1063 #ifdef CONFIG_GLUSTERFS_FALLOCATE 1064 case PREALLOC_MODE_FALLOC: 1065 if (glfs_fallocate(fd, 0, current_length, offset - current_length)) { 1066 error_setg_errno(errp, errno, "Could not preallocate data"); 1067 return -errno; 1068 } 1069 break; 1070 #endif /* CONFIG_GLUSTERFS_FALLOCATE */ 1071 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1072 case PREALLOC_MODE_FULL: 1073 if (glfs_ftruncate(fd, offset)) { 1074 error_setg_errno(errp, errno, "Could not resize file"); 1075 return -errno; 1076 } 1077 if (glfs_zerofill(fd, current_length, offset - current_length)) { 1078 error_setg_errno(errp, errno, "Could not zerofill the new area"); 1079 return -errno; 1080 } 1081 break; 1082 #endif /* CONFIG_GLUSTERFS_ZEROFILL */ 1083 case PREALLOC_MODE_OFF: 1084 if (glfs_ftruncate(fd, offset)) { 1085 error_setg_errno(errp, errno, "Could not resize file"); 1086 return -errno; 1087 } 1088 break; 1089 default: 1090 error_setg(errp, "Unsupported preallocation mode: %s", 1091 PreallocMode_str(prealloc)); 1092 return -EINVAL; 1093 } 1094 1095 return 0; 1096 } 1097 1098 static int qemu_gluster_co_create(BlockdevCreateOptions *options, 1099 Error **errp) 1100 { 1101 BlockdevCreateOptionsGluster *opts = &options->u.gluster; 1102 struct glfs *glfs; 1103 struct glfs_fd *fd = NULL; 1104 int ret = 0; 1105 1106 assert(options->driver == BLOCKDEV_DRIVER_GLUSTER); 1107 1108 glfs = qemu_gluster_glfs_init(opts->location, errp); 1109 if (!glfs) { 1110 ret = -errno; 1111 goto out; 1112 } 1113 1114 fd = glfs_creat(glfs, opts->location->path, 1115 O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, S_IRUSR | S_IWUSR); 1116 if (!fd) { 1117 ret = -errno; 1118 goto out; 1119 } 1120 1121 ret = qemu_gluster_do_truncate(fd, opts->size, opts->preallocation, errp); 1122 1123 out: 1124 if (fd) { 1125 if (glfs_close(fd) != 0 && ret == 0) { 1126 ret = -errno; 1127 } 1128 } 1129 glfs_clear_preopened(glfs); 1130 return ret; 1131 } 1132 1133 static int coroutine_fn qemu_gluster_co_create_opts(const char *filename, 1134 QemuOpts *opts, 1135 Error **errp) 1136 { 1137 BlockdevCreateOptions *options; 1138 BlockdevCreateOptionsGluster *gopts; 1139 BlockdevOptionsGluster *gconf; 1140 char *tmp = NULL; 1141 Error *local_err = NULL; 1142 int ret; 1143 1144 options = g_new0(BlockdevCreateOptions, 1); 1145 options->driver = BLOCKDEV_DRIVER_GLUSTER; 1146 gopts = &options->u.gluster; 1147 1148 gconf = g_new0(BlockdevOptionsGluster, 1); 1149 gopts->location = gconf; 1150 1151 gopts->size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0), 1152 BDRV_SECTOR_SIZE); 1153 1154 tmp = qemu_opt_get_del(opts, BLOCK_OPT_PREALLOC); 1155 gopts->preallocation = qapi_enum_parse(&PreallocMode_lookup, tmp, 1156 PREALLOC_MODE_OFF, &local_err); 1157 g_free(tmp); 1158 if (local_err) { 1159 error_propagate(errp, local_err); 1160 ret = -EINVAL; 1161 goto fail; 1162 } 1163 1164 gconf->debug = qemu_opt_get_number_del(opts, GLUSTER_OPT_DEBUG, 1165 GLUSTER_DEBUG_DEFAULT); 1166 if (gconf->debug < 0) { 1167 gconf->debug = 0; 1168 } else if (gconf->debug > GLUSTER_DEBUG_MAX) { 1169 gconf->debug = GLUSTER_DEBUG_MAX; 1170 } 1171 gconf->has_debug = true; 1172 1173 gconf->logfile = qemu_opt_get_del(opts, GLUSTER_OPT_LOGFILE); 1174 if (!gconf->logfile) { 1175 gconf->logfile = g_strdup(GLUSTER_LOGFILE_DEFAULT); 1176 } 1177 gconf->has_logfile = true; 1178 1179 ret = qemu_gluster_parse(gconf, filename, NULL, errp); 1180 if (ret < 0) { 1181 goto fail; 1182 } 1183 1184 ret = qemu_gluster_co_create(options, errp); 1185 if (ret < 0) { 1186 goto fail; 1187 } 1188 1189 ret = 0; 1190 fail: 1191 qapi_free_BlockdevCreateOptions(options); 1192 return ret; 1193 } 1194 1195 static coroutine_fn int qemu_gluster_co_rw(BlockDriverState *bs, 1196 int64_t sector_num, int nb_sectors, 1197 QEMUIOVector *qiov, int write) 1198 { 1199 int ret; 1200 GlusterAIOCB acb; 1201 BDRVGlusterState *s = bs->opaque; 1202 size_t size = nb_sectors * BDRV_SECTOR_SIZE; 1203 off_t offset = sector_num * BDRV_SECTOR_SIZE; 1204 1205 acb.size = size; 1206 acb.ret = 0; 1207 acb.coroutine = qemu_coroutine_self(); 1208 acb.aio_context = bdrv_get_aio_context(bs); 1209 1210 if (write) { 1211 ret = glfs_pwritev_async(s->fd, qiov->iov, qiov->niov, offset, 0, 1212 gluster_finish_aiocb, &acb); 1213 } else { 1214 ret = glfs_preadv_async(s->fd, qiov->iov, qiov->niov, offset, 0, 1215 gluster_finish_aiocb, &acb); 1216 } 1217 1218 if (ret < 0) { 1219 return -errno; 1220 } 1221 1222 qemu_coroutine_yield(); 1223 return acb.ret; 1224 } 1225 1226 static coroutine_fn int qemu_gluster_co_truncate(BlockDriverState *bs, 1227 int64_t offset, 1228 PreallocMode prealloc, 1229 Error **errp) 1230 { 1231 BDRVGlusterState *s = bs->opaque; 1232 return qemu_gluster_do_truncate(s->fd, offset, prealloc, errp); 1233 } 1234 1235 static coroutine_fn int qemu_gluster_co_readv(BlockDriverState *bs, 1236 int64_t sector_num, 1237 int nb_sectors, 1238 QEMUIOVector *qiov) 1239 { 1240 return qemu_gluster_co_rw(bs, sector_num, nb_sectors, qiov, 0); 1241 } 1242 1243 static coroutine_fn int qemu_gluster_co_writev(BlockDriverState *bs, 1244 int64_t sector_num, 1245 int nb_sectors, 1246 QEMUIOVector *qiov, 1247 int flags) 1248 { 1249 assert(!flags); 1250 return qemu_gluster_co_rw(bs, sector_num, nb_sectors, qiov, 1); 1251 } 1252 1253 static void qemu_gluster_close(BlockDriverState *bs) 1254 { 1255 BDRVGlusterState *s = bs->opaque; 1256 1257 g_free(s->logfile); 1258 if (s->fd) { 1259 glfs_close(s->fd); 1260 s->fd = NULL; 1261 } 1262 glfs_clear_preopened(s->glfs); 1263 } 1264 1265 static coroutine_fn int qemu_gluster_co_flush_to_disk(BlockDriverState *bs) 1266 { 1267 int ret; 1268 GlusterAIOCB acb; 1269 BDRVGlusterState *s = bs->opaque; 1270 1271 acb.size = 0; 1272 acb.ret = 0; 1273 acb.coroutine = qemu_coroutine_self(); 1274 acb.aio_context = bdrv_get_aio_context(bs); 1275 1276 ret = glfs_fsync_async(s->fd, gluster_finish_aiocb, &acb); 1277 if (ret < 0) { 1278 ret = -errno; 1279 goto error; 1280 } 1281 1282 qemu_coroutine_yield(); 1283 if (acb.ret < 0) { 1284 ret = acb.ret; 1285 goto error; 1286 } 1287 1288 return acb.ret; 1289 1290 error: 1291 /* Some versions of Gluster (3.5.6 -> 3.5.8?) will not retain its cache 1292 * after a fsync failure, so we have no way of allowing the guest to safely 1293 * continue. Gluster versions prior to 3.5.6 don't retain the cache 1294 * either, but will invalidate the fd on error, so this is again our only 1295 * option. 1296 * 1297 * The 'resync-failed-syncs-after-fsync' xlator option for the 1298 * write-behind cache will cause later gluster versions to retain its 1299 * cache after error, so long as the fd remains open. However, we 1300 * currently have no way of knowing if this option is supported. 1301 * 1302 * TODO: Once gluster provides a way for us to determine if the option 1303 * is supported, bypass the closure and setting drv to NULL. */ 1304 qemu_gluster_close(bs); 1305 bs->drv = NULL; 1306 return ret; 1307 } 1308 1309 #ifdef CONFIG_GLUSTERFS_DISCARD 1310 static coroutine_fn int qemu_gluster_co_pdiscard(BlockDriverState *bs, 1311 int64_t offset, int size) 1312 { 1313 int ret; 1314 GlusterAIOCB acb; 1315 BDRVGlusterState *s = bs->opaque; 1316 1317 acb.size = 0; 1318 acb.ret = 0; 1319 acb.coroutine = qemu_coroutine_self(); 1320 acb.aio_context = bdrv_get_aio_context(bs); 1321 1322 ret = glfs_discard_async(s->fd, offset, size, gluster_finish_aiocb, &acb); 1323 if (ret < 0) { 1324 return -errno; 1325 } 1326 1327 qemu_coroutine_yield(); 1328 return acb.ret; 1329 } 1330 #endif 1331 1332 static int64_t qemu_gluster_getlength(BlockDriverState *bs) 1333 { 1334 BDRVGlusterState *s = bs->opaque; 1335 int64_t ret; 1336 1337 ret = glfs_lseek(s->fd, 0, SEEK_END); 1338 if (ret < 0) { 1339 return -errno; 1340 } else { 1341 return ret; 1342 } 1343 } 1344 1345 static int64_t qemu_gluster_allocated_file_size(BlockDriverState *bs) 1346 { 1347 BDRVGlusterState *s = bs->opaque; 1348 struct stat st; 1349 int ret; 1350 1351 ret = glfs_fstat(s->fd, &st); 1352 if (ret < 0) { 1353 return -errno; 1354 } else { 1355 return st.st_blocks * 512; 1356 } 1357 } 1358 1359 static int qemu_gluster_has_zero_init(BlockDriverState *bs) 1360 { 1361 /* GlusterFS volume could be backed by a block device */ 1362 return 0; 1363 } 1364 1365 /* 1366 * Find allocation range in @bs around offset @start. 1367 * May change underlying file descriptor's file offset. 1368 * If @start is not in a hole, store @start in @data, and the 1369 * beginning of the next hole in @hole, and return 0. 1370 * If @start is in a non-trailing hole, store @start in @hole and the 1371 * beginning of the next non-hole in @data, and return 0. 1372 * If @start is in a trailing hole or beyond EOF, return -ENXIO. 1373 * If we can't find out, return a negative errno other than -ENXIO. 1374 * 1375 * (Shamefully copied from file-posix.c, only minuscule adaptions.) 1376 */ 1377 static int find_allocation(BlockDriverState *bs, off_t start, 1378 off_t *data, off_t *hole) 1379 { 1380 BDRVGlusterState *s = bs->opaque; 1381 1382 if (!s->supports_seek_data) { 1383 goto exit; 1384 } 1385 1386 #if defined SEEK_HOLE && defined SEEK_DATA 1387 off_t offs; 1388 1389 /* 1390 * SEEK_DATA cases: 1391 * D1. offs == start: start is in data 1392 * D2. offs > start: start is in a hole, next data at offs 1393 * D3. offs < 0, errno = ENXIO: either start is in a trailing hole 1394 * or start is beyond EOF 1395 * If the latter happens, the file has been truncated behind 1396 * our back since we opened it. All bets are off then. 1397 * Treating like a trailing hole is simplest. 1398 * D4. offs < 0, errno != ENXIO: we learned nothing 1399 */ 1400 offs = glfs_lseek(s->fd, start, SEEK_DATA); 1401 if (offs < 0) { 1402 return -errno; /* D3 or D4 */ 1403 } 1404 1405 if (offs < start) { 1406 /* This is not a valid return by lseek(). We are safe to just return 1407 * -EIO in this case, and we'll treat it like D4. Unfortunately some 1408 * versions of gluster server will return offs < start, so an assert 1409 * here will unnecessarily abort QEMU. */ 1410 return -EIO; 1411 } 1412 1413 if (offs > start) { 1414 /* D2: in hole, next data at offs */ 1415 *hole = start; 1416 *data = offs; 1417 return 0; 1418 } 1419 1420 /* D1: in data, end not yet known */ 1421 1422 /* 1423 * SEEK_HOLE cases: 1424 * H1. offs == start: start is in a hole 1425 * If this happens here, a hole has been dug behind our back 1426 * since the previous lseek(). 1427 * H2. offs > start: either start is in data, next hole at offs, 1428 * or start is in trailing hole, EOF at offs 1429 * Linux treats trailing holes like any other hole: offs == 1430 * start. Solaris seeks to EOF instead: offs > start (blech). 1431 * If that happens here, a hole has been dug behind our back 1432 * since the previous lseek(). 1433 * H3. offs < 0, errno = ENXIO: start is beyond EOF 1434 * If this happens, the file has been truncated behind our 1435 * back since we opened it. Treat it like a trailing hole. 1436 * H4. offs < 0, errno != ENXIO: we learned nothing 1437 * Pretend we know nothing at all, i.e. "forget" about D1. 1438 */ 1439 offs = glfs_lseek(s->fd, start, SEEK_HOLE); 1440 if (offs < 0) { 1441 return -errno; /* D1 and (H3 or H4) */ 1442 } 1443 1444 if (offs < start) { 1445 /* This is not a valid return by lseek(). We are safe to just return 1446 * -EIO in this case, and we'll treat it like H4. Unfortunately some 1447 * versions of gluster server will return offs < start, so an assert 1448 * here will unnecessarily abort QEMU. */ 1449 return -EIO; 1450 } 1451 1452 if (offs > start) { 1453 /* 1454 * D1 and H2: either in data, next hole at offs, or it was in 1455 * data but is now in a trailing hole. In the latter case, 1456 * all bets are off. Treating it as if it there was data all 1457 * the way to EOF is safe, so simply do that. 1458 */ 1459 *data = start; 1460 *hole = offs; 1461 return 0; 1462 } 1463 1464 /* D1 and H1 */ 1465 return -EBUSY; 1466 #endif 1467 1468 exit: 1469 return -ENOTSUP; 1470 } 1471 1472 /* 1473 * Returns the allocation status of the specified offset. 1474 * 1475 * The block layer guarantees 'offset' and 'bytes' are within bounds. 1476 * 1477 * 'pnum' is set to the number of bytes (including and immediately following 1478 * the specified offset) that are known to be in the same 1479 * allocated/unallocated state. 1480 * 1481 * 'bytes' is the max value 'pnum' should be set to. 1482 * 1483 * (Based on raw_co_block_status() from file-posix.c.) 1484 */ 1485 static int coroutine_fn qemu_gluster_co_block_status(BlockDriverState *bs, 1486 bool want_zero, 1487 int64_t offset, 1488 int64_t bytes, 1489 int64_t *pnum, 1490 int64_t *map, 1491 BlockDriverState **file) 1492 { 1493 BDRVGlusterState *s = bs->opaque; 1494 off_t data = 0, hole = 0; 1495 int ret = -EINVAL; 1496 1497 if (!s->fd) { 1498 return ret; 1499 } 1500 1501 if (!want_zero) { 1502 *pnum = bytes; 1503 *map = offset; 1504 *file = bs; 1505 return BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID; 1506 } 1507 1508 ret = find_allocation(bs, offset, &data, &hole); 1509 if (ret == -ENXIO) { 1510 /* Trailing hole */ 1511 *pnum = bytes; 1512 ret = BDRV_BLOCK_ZERO; 1513 } else if (ret < 0) { 1514 /* No info available, so pretend there are no holes */ 1515 *pnum = bytes; 1516 ret = BDRV_BLOCK_DATA; 1517 } else if (data == offset) { 1518 /* On a data extent, compute bytes to the end of the extent, 1519 * possibly including a partial sector at EOF. */ 1520 *pnum = MIN(bytes, hole - offset); 1521 ret = BDRV_BLOCK_DATA; 1522 } else { 1523 /* On a hole, compute bytes to the beginning of the next extent. */ 1524 assert(hole == offset); 1525 *pnum = MIN(bytes, data - offset); 1526 ret = BDRV_BLOCK_ZERO; 1527 } 1528 1529 *map = offset; 1530 *file = bs; 1531 1532 return ret | BDRV_BLOCK_OFFSET_VALID; 1533 } 1534 1535 1536 static const char *const gluster_strong_open_opts[] = { 1537 GLUSTER_OPT_VOLUME, 1538 GLUSTER_OPT_PATH, 1539 GLUSTER_OPT_TYPE, 1540 GLUSTER_OPT_SERVER_PATTERN, 1541 GLUSTER_OPT_HOST, 1542 GLUSTER_OPT_PORT, 1543 GLUSTER_OPT_TO, 1544 GLUSTER_OPT_IPV4, 1545 GLUSTER_OPT_IPV6, 1546 GLUSTER_OPT_SOCKET, 1547 1548 NULL 1549 }; 1550 1551 static BlockDriver bdrv_gluster = { 1552 .format_name = "gluster", 1553 .protocol_name = "gluster", 1554 .instance_size = sizeof(BDRVGlusterState), 1555 .bdrv_needs_filename = false, 1556 .bdrv_file_open = qemu_gluster_open, 1557 .bdrv_reopen_prepare = qemu_gluster_reopen_prepare, 1558 .bdrv_reopen_commit = qemu_gluster_reopen_commit, 1559 .bdrv_reopen_abort = qemu_gluster_reopen_abort, 1560 .bdrv_close = qemu_gluster_close, 1561 .bdrv_co_create = qemu_gluster_co_create, 1562 .bdrv_co_create_opts = qemu_gluster_co_create_opts, 1563 .bdrv_getlength = qemu_gluster_getlength, 1564 .bdrv_get_allocated_file_size = qemu_gluster_allocated_file_size, 1565 .bdrv_co_truncate = qemu_gluster_co_truncate, 1566 .bdrv_co_readv = qemu_gluster_co_readv, 1567 .bdrv_co_writev = qemu_gluster_co_writev, 1568 .bdrv_co_flush_to_disk = qemu_gluster_co_flush_to_disk, 1569 .bdrv_has_zero_init = qemu_gluster_has_zero_init, 1570 .bdrv_has_zero_init_truncate = qemu_gluster_has_zero_init, 1571 #ifdef CONFIG_GLUSTERFS_DISCARD 1572 .bdrv_co_pdiscard = qemu_gluster_co_pdiscard, 1573 #endif 1574 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1575 .bdrv_co_pwrite_zeroes = qemu_gluster_co_pwrite_zeroes, 1576 #endif 1577 .bdrv_co_block_status = qemu_gluster_co_block_status, 1578 .bdrv_refresh_limits = qemu_gluster_refresh_limits, 1579 .create_opts = &qemu_gluster_create_opts, 1580 .strong_runtime_opts = gluster_strong_open_opts, 1581 }; 1582 1583 static BlockDriver bdrv_gluster_tcp = { 1584 .format_name = "gluster", 1585 .protocol_name = "gluster+tcp", 1586 .instance_size = sizeof(BDRVGlusterState), 1587 .bdrv_needs_filename = false, 1588 .bdrv_file_open = qemu_gluster_open, 1589 .bdrv_reopen_prepare = qemu_gluster_reopen_prepare, 1590 .bdrv_reopen_commit = qemu_gluster_reopen_commit, 1591 .bdrv_reopen_abort = qemu_gluster_reopen_abort, 1592 .bdrv_close = qemu_gluster_close, 1593 .bdrv_co_create = qemu_gluster_co_create, 1594 .bdrv_co_create_opts = qemu_gluster_co_create_opts, 1595 .bdrv_getlength = qemu_gluster_getlength, 1596 .bdrv_get_allocated_file_size = qemu_gluster_allocated_file_size, 1597 .bdrv_co_truncate = qemu_gluster_co_truncate, 1598 .bdrv_co_readv = qemu_gluster_co_readv, 1599 .bdrv_co_writev = qemu_gluster_co_writev, 1600 .bdrv_co_flush_to_disk = qemu_gluster_co_flush_to_disk, 1601 .bdrv_has_zero_init = qemu_gluster_has_zero_init, 1602 .bdrv_has_zero_init_truncate = qemu_gluster_has_zero_init, 1603 #ifdef CONFIG_GLUSTERFS_DISCARD 1604 .bdrv_co_pdiscard = qemu_gluster_co_pdiscard, 1605 #endif 1606 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1607 .bdrv_co_pwrite_zeroes = qemu_gluster_co_pwrite_zeroes, 1608 #endif 1609 .bdrv_co_block_status = qemu_gluster_co_block_status, 1610 .bdrv_refresh_limits = qemu_gluster_refresh_limits, 1611 .create_opts = &qemu_gluster_create_opts, 1612 .strong_runtime_opts = gluster_strong_open_opts, 1613 }; 1614 1615 static BlockDriver bdrv_gluster_unix = { 1616 .format_name = "gluster", 1617 .protocol_name = "gluster+unix", 1618 .instance_size = sizeof(BDRVGlusterState), 1619 .bdrv_needs_filename = true, 1620 .bdrv_file_open = qemu_gluster_open, 1621 .bdrv_reopen_prepare = qemu_gluster_reopen_prepare, 1622 .bdrv_reopen_commit = qemu_gluster_reopen_commit, 1623 .bdrv_reopen_abort = qemu_gluster_reopen_abort, 1624 .bdrv_close = qemu_gluster_close, 1625 .bdrv_co_create = qemu_gluster_co_create, 1626 .bdrv_co_create_opts = qemu_gluster_co_create_opts, 1627 .bdrv_getlength = qemu_gluster_getlength, 1628 .bdrv_get_allocated_file_size = qemu_gluster_allocated_file_size, 1629 .bdrv_co_truncate = qemu_gluster_co_truncate, 1630 .bdrv_co_readv = qemu_gluster_co_readv, 1631 .bdrv_co_writev = qemu_gluster_co_writev, 1632 .bdrv_co_flush_to_disk = qemu_gluster_co_flush_to_disk, 1633 .bdrv_has_zero_init = qemu_gluster_has_zero_init, 1634 .bdrv_has_zero_init_truncate = qemu_gluster_has_zero_init, 1635 #ifdef CONFIG_GLUSTERFS_DISCARD 1636 .bdrv_co_pdiscard = qemu_gluster_co_pdiscard, 1637 #endif 1638 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1639 .bdrv_co_pwrite_zeroes = qemu_gluster_co_pwrite_zeroes, 1640 #endif 1641 .bdrv_co_block_status = qemu_gluster_co_block_status, 1642 .bdrv_refresh_limits = qemu_gluster_refresh_limits, 1643 .create_opts = &qemu_gluster_create_opts, 1644 .strong_runtime_opts = gluster_strong_open_opts, 1645 }; 1646 1647 /* rdma is deprecated (actually never supported for volfile fetch). 1648 * Let's maintain it for the protocol compatibility, to make sure things 1649 * won't break immediately. For now, gluster+rdma will fall back to gluster+tcp 1650 * protocol with a warning. 1651 * TODO: remove gluster+rdma interface support 1652 */ 1653 static BlockDriver bdrv_gluster_rdma = { 1654 .format_name = "gluster", 1655 .protocol_name = "gluster+rdma", 1656 .instance_size = sizeof(BDRVGlusterState), 1657 .bdrv_needs_filename = true, 1658 .bdrv_file_open = qemu_gluster_open, 1659 .bdrv_reopen_prepare = qemu_gluster_reopen_prepare, 1660 .bdrv_reopen_commit = qemu_gluster_reopen_commit, 1661 .bdrv_reopen_abort = qemu_gluster_reopen_abort, 1662 .bdrv_close = qemu_gluster_close, 1663 .bdrv_co_create = qemu_gluster_co_create, 1664 .bdrv_co_create_opts = qemu_gluster_co_create_opts, 1665 .bdrv_getlength = qemu_gluster_getlength, 1666 .bdrv_get_allocated_file_size = qemu_gluster_allocated_file_size, 1667 .bdrv_co_truncate = qemu_gluster_co_truncate, 1668 .bdrv_co_readv = qemu_gluster_co_readv, 1669 .bdrv_co_writev = qemu_gluster_co_writev, 1670 .bdrv_co_flush_to_disk = qemu_gluster_co_flush_to_disk, 1671 .bdrv_has_zero_init = qemu_gluster_has_zero_init, 1672 .bdrv_has_zero_init_truncate = qemu_gluster_has_zero_init, 1673 #ifdef CONFIG_GLUSTERFS_DISCARD 1674 .bdrv_co_pdiscard = qemu_gluster_co_pdiscard, 1675 #endif 1676 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1677 .bdrv_co_pwrite_zeroes = qemu_gluster_co_pwrite_zeroes, 1678 #endif 1679 .bdrv_co_block_status = qemu_gluster_co_block_status, 1680 .bdrv_refresh_limits = qemu_gluster_refresh_limits, 1681 .create_opts = &qemu_gluster_create_opts, 1682 .strong_runtime_opts = gluster_strong_open_opts, 1683 }; 1684 1685 static void bdrv_gluster_init(void) 1686 { 1687 bdrv_register(&bdrv_gluster_rdma); 1688 bdrv_register(&bdrv_gluster_unix); 1689 bdrv_register(&bdrv_gluster_tcp); 1690 bdrv_register(&bdrv_gluster); 1691 } 1692 1693 block_init(bdrv_gluster_init); 1694